source: pacpussensors/trunk/Vislab/lib3dv/eigen/Eigen/OrderingMethods@ 136

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1#ifndef EIGEN_ORDERINGMETHODS_MODULE_H
2#define EIGEN_ORDERINGMETHODS_MODULE_H
3
4#include "SparseCore"
5
6#include "src/Core/util/DisableStupidWarnings.h"
7
8/**
9 * \defgroup OrderingMethods_Module OrderingMethods module
10 *
11 * This module is currently for internal use only
12 *
13 * It defines various built-in and external ordering methods for sparse matrices.
14 * They are typically used to reduce the number of elements during
15 * the sparse matrix decomposition (LLT, LU, QR).
16 * Precisely, in a preprocessing step, a permutation matrix P is computed using
17 * those ordering methods and applied to the columns of the matrix.
18 * Using for instance the sparse Cholesky decomposition, it is expected that
19 * the nonzeros elements in LLT(A*P) will be much smaller than that in LLT(A).
20 *
21 *
22 * Usage :
23 * \code
24 * #include <Eigen/OrderingMethods>
25 * \endcode
26 *
27 * A simple usage is as a template parameter in the sparse decomposition classes :
28 *
29 * \code
30 * SparseLU<MatrixType, COLAMDOrdering<int> > solver;
31 * \endcode
32 *
33 * \code
34 * SparseQR<MatrixType, COLAMDOrdering<int> > solver;
35 * \endcode
36 *
37 * It is possible as well to call directly a particular ordering method for your own purpose,
38 * \code
39 * AMDOrdering<int> ordering;
40 * PermutationMatrix<Dynamic, Dynamic, int> perm;
41 * SparseMatrix<double> A;
42 * //Fill the matrix ...
43 *
44 * ordering(A, perm); // Call AMD
45 * \endcode
46 *
47 * \note Some of these methods (like AMD or METIS), need the sparsity pattern
48 * of the input matrix to be symmetric. When the matrix is structurally unsymmetric,
49 * Eigen computes internally the pattern of \f$A^T*A\f$ before calling the method.
50 * If your matrix is already symmetric (at leat in structure), you can avoid that
51 * by calling the method with a SelfAdjointView type.
52 *
53 * \code
54 * // Call the ordering on the pattern of the lower triangular matrix A
55 * ordering(A.selfadjointView<Lower>(), perm);
56 * \endcode
57 */
58
59#ifndef EIGEN_MPL2_ONLY
60#include "src/OrderingMethods/Amd.h"
61#endif
62
63#include "src/OrderingMethods/Ordering.h"
64#include "src/Core/util/ReenableStupidWarnings.h"
65
66#endif // EIGEN_ORDERINGMETHODS_MODULE_H
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